Thin chassis near field communication (nfc) antenna integration

ABSTRACT

Described herein are techniques related one or more systems, apparatuses, methods, etc. for integrating a near field communications (NFC) coil antenna in a portable device. For example, the NFC antenna is integrated under a metal chassis of the portable device. The metal chassis and a conductive coating—that is integrated underneath the full metal chassis—are designed to include one or more slots to provide high impedance to Eddy current induced in the conductive coating.

BACKGROUND

Recently, technologies have arisen that allow near field coupling (e.g.,wireless power transfers (WPT) and near field communications (NFC))between portable devices in close proximity to each other. Such nearfield coupling functions may use radio frequency (RF) antennas in thedevices to transmit and receive electromagnetic signals. Because of userdesires (and/or for esthetic reasons) many of these portable devices aresmall (and becoming smaller), and tend to have exaggerated aspect ratioswhen viewed from the side. As a result, many of these portable devicesincorporate flat antennas, which use coils of conductive material astheir radiating antennas for use in near field coupling functions.

For example, an NFC antenna integration in a plastic chassis portabledevice may be achieved by creating a cutout on a conductiveelectromagnetic interference (EMI) coating under a palm rest area of theportable device, such that the NFC antenna that is attached to thecutout area may radiate through the chassis effectively. For deviceshaving a complete metallic chassis, the metallic chassis is often usedto maintain mechanical strength in a thin design. The use of themetallic chassis creates a key challenge for NFC coil antennaintegration into such devices (e.g., thin laptop computer such asUltrabooks), since the NFC antenna needs a non-metallic surface in orderto radiate through.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates portable devices in an example near field couplingarrangement.

FIGS. 2A and 2B illustrate an example near field communications (NFC)coil antenna and top view of a keypad area in a portable device,respectively.

FIG. 3A illustrates an example underneath view of a coil antenna and aconductive surface of a conductive coating.

FIG. 3B illustrates an example upside down view of a coil antenna and aconductive coating with one or more slots.

FIG. 4 illustrates an example near field communications (NFC) relatedoperation.

FIGS. 5A to 5D illustrate example locations for one or more groundingpoints to provide electrostatic discharge (ESD) protection.

FIGS. 6A and 6B illustrate example slot configurations in a conductivecoating to provide high impedance to an induced current.

FIG. 7 is an example method to facilitate near field communications(NFC) coil antenna integration in a full metal chassis portable device.

The following Detailed Description is provided with reference to theaccompanying figures. In the figures, the left-most digit(s) of areference number usually identifies the figure in which the referencenumber first appears. The use of the same reference numbers in differentfigures indicates similar or identical items.

DETAILED DESCRIPTION

This document discloses one or more systems, apparatuses, methods, etc.for integrating a near field communications (NFC) coil antenna in aportable device such as, in a palm rest of a full metal chassis portabledevice (e.g., Ultrabook). In an implementation, the NFC coil antenna mayinclude continuous multiple loops to form a ring shaped antenna (e.g.,rectangular shape). In this implementation, the NFC coil antenna may bedirectly integrated underneath the full metal chassis of the portabledevice. For example, the full metal chassis may be configured to utilizea special pattern or design to reduce Eddy currents that may be inducedby electromagnetic fields radiated by the NFC coil antenna. In thisexample, the special pattern or design may include construction of oneor more slots in the full metal chassis such that the one or more slotsmay include segments or slices that extend from the full metal chassisto a conductive coating which is embedded or attached to the full metalchassis. In an implementation, the one or more slots are configured tobe perpendicular to an assumed direction of the Eddy current. Forexample, if the Eddy current is calculated to have a curvaturedirection, then the one or more slots may be configured to adopt andfollow the curvature direction of the Eddy current to maintain theperpendicular configuration. The perpendicular configuration of the oneor more slots may provide high impedance to the Eddy current. As such,the conductive coating is transformed into a transparent conductivecoating as a result of the minimized presence of the Eddy current.Furthermore, an area in the conductive coating that is defined by theone or more slots may contain one or more grounding points to maintainelectrostatic discharge (ESD) protection. For example, if the areacovered by the one or more slots is rectangular in shape, then the oneor more grounding points may be located in a middle of at least one sideof the rectangular shape area.

FIG. 1 illustrates an example arrangement 100 of portable devices fornear field coupling. More particularly, users may have a desire tooperate near field coupling enabled portable electronic devices and/orother devices in certain ergonomically convenient manners. Examples ofsuch portable devices include, but are not limited to, ultrabooks, atablet computer, a netbook, a notebook computer, a laptop computer,mobile phone, a cellular phone, a smartphone, a personal digitalassistant, a multimedia playback device, a digital music player, adigital video player, a navigational device, a digital camera, and thelike.

In an implementation, FIG. 1 shows two users (not shown) that operatetheir NFC-enabled portable devices 102-2 and 102-4 to performNFC-related information sharing functions. For example, a front-to-back(not shown), or a back-to-back (not shown) manner may be performed forthe NFC communication. In an implementation, the portable devices 102may accept information from a credit card 104, a NFC tag 106 (or othersimilar device) through a NFC coil antenna (not shown). The portabledevices 102 may require the NFC coil antenna (not shown) to beintegrated in a palm rest (not shown) or in other areas of the portabledevices 102. For example, the NFC coil antenna (not shown) may beintegrated underneath a metal chassis of portable device 102, or the NFCcoil antenna (not shown) may be integrated underneath conductive coatingof the portable device 102. In this example, the portable devices 102may accept information from a credit card 104 or NFC tag 106 through theNFC coil antenna (not shown).

FIG. 2A illustrates an example NFC coil antenna 200. In animplementation, the coil antenna 200 may include a continuous multipleloop of coil antenna that forms a rectangular ring shape. The continuousloop of coil antenna 200 may be mounted on, embedded in, or otherwiseassociated with a metallic chassis (not shown) or a conductive coatingof a plastic chassis device, such as portable device 102. The coilantenna 200 may include a dedicated antenna for NFC purposes. In otherwords, the coil antenna 200 may be configured to operate on a separateresonant frequency (e.g., 13.56 MHz to implement NFC operations), andindependent from another antenna that uses standard frequencies used inwireless communications (e.g., 5 GHz for WiFi signals). The coil antenna200 may be made out of a printed circuit board (PCB), a flexible printedcircuit (FPC), a metal wire, created through a laser direct structuring(LDS) process, or directly embedded to the metallic chassis (not shown)and underneath a conductive coating (not shown) portable device 102.

FIG. 2B illustrates a top view of a keypad area 202 of the portabledevice 102. In an implementation, the present embodiment may include aunique pattern and design of the conductive coating (not shown) that isassociated with or located underneath chassis 204. In thisimplementation, the conductive coating (not shown) may be associatedwith chassis 204. Chassis 204 may be plastic or full metal. For example,in a full metallic chassis, the unique pattern and design may beimplemented to extend from the conductive coating (not shown) of chassis204. In a full metallic chassis 204, the unique pattern and design maybe implemented by providing slots in the metallic chassis 204. Forplastic chassis 204, the unique pattern and design may extend to theconductive coating (not shown) alone. In an implementation, the uniquepattern and design may include construction of one or more slots (notshown) in the chassis 204 to allow the coil antenna 200 to perform NFCrelated functions.

In an implementation, an NFC module 206 may be integrated anywhereinside the keypad area 202 or in other areas such us, beside a trackpadarea 208. The NFC module 206 may include transceiver circuitry thatprocesses electrical signals in the coil antenna 200. For example, theNFC module 206 may be used to provide tuning to the coil antenna 200 formaximum power transfer during transmit or receive operations. In otherimplementations, the NFC module 206 may be integrated with the coilantenna 200 underneath the chassis 204 to form a single module.

FIGS. 3A and 3B illustrate an underneath view of the coil antenna 200integration in the chassis 204. For example, the coil antenna 200 isplaced underneath the full metal chassis 204 that includes an integratedor associated conductive coating 300. In this example, the integrated orassociated conductive coating 300 is located between the coil antenna200 and the chassis 204. FIG. 3A and FIG. 3B shows the underneath ofthis configuration (i.e., chassis 204 at bottom and coil antenna 200 attop).

With continuing reference to FIG. 3A which may be prior artconfiguration, when a current 302 is injected through the coil antenna200, an electromagnetic field (not shown) may be generated around thecoil antenna 200. In an implementation, the electromagnetic field (notshown) may induce an Eddy current 304 in a conductive surface 306 of theconductive coating 300. In this implementation, the Eddy current 304 isflowing in opposite direction as against the direction of the injectedcurrent 302. As a result, the Eddy current 304 may generate a reactivemagnetic field (not shown) that may partially cancel the electromagneticfield (not shown) generated by the coil antenna 200. To this end, theNFC performance of the coil antenna 200 is significantly impacted. Inother words, such as in a full metal chassis 204, impedance (not shown)seen by the Eddy current 304 is approximately zero, and thus the inducedEddy current 304 magnitude is high. The higher the Eddy current 304, thelower NFC field strength (not shown) is produced in the coil antenna200.

With continuing reference to FIG. 3B, the special pattern or design forthe conductive coating 300 may minimize presence of the Eddy current304. For example, the special pattern or design may include constructionor insertion of one or more slots 308 to reduce coupling between thecoil antenna 200 and the conductive coating 300. In an implementation,the one or more slots 308 may include segments or slices that areconstructed to be perpendicular in direction to the Eddy current 304. Inthis implementation, the perpendicular configuration of the one or moreslots 308 may provide high impedance or electrical resistance to theEddy current 304. The high impedance may reduce the Eddy current 304 andas such, the NFC field strength for the coil antenna 200 is increased.

In an implementation, such as in plastic chassis (e.g., chassis 204),the one or more slots 308 may be constructed at the conductive coating300 alone. On the other hand, in case of full metal chassis 204, the oneor more slots 308 may be constructed to extend from the full metalchassis 204 to the integrated conductive coating 300 that is locatedunderneath the full metal chassis 204.

FIG. 4 illustrates an example NFC related operation of the coil antenna200. In an implementation, a coil antenna 200-2 may include the coilantenna for the credit card 104 or the NFC tag 106, while the coilantenna 200-4 may include another coil antenna for the portable device102. In this implementation, the credit card 104 or the NFC tag 106 isread by the coil antenna 200-4 through the one or more slots 308. In animplementation, the one or more slots 308 may transform the conductivecoating 300 into a transparent conductive coating 300 such that theintegrated coil antenna 200-4 may perform NFC related functions as ifthe conductive coating 300 is not present. In other words, theconductive coating 300 may include a low coupling coefficient such thatthe coil antenna 200-4 may be able to read the credit card 104 or theNFC tag 106 without compromising ESD protection for the conductivecoating 300.

FIG. 5A and FIG. 5B illustrate an example locations for grounding pointsin the slots 308. In an implementation, the one or more slots 308 may beconstructed within an area defined by area 500 (of the conductivecoating 300). In this implementation, the area 500 may be defined atleast by extent of the electromagnetic field (not shown) that isgenerated by the coil antenna 200-4 during the NFC related operationsbetween the coil antenna 200-4 and/or coil antenna 200-2. For example,if the extent of the electromagnetic field (not shown) may include atleast the area covered by the area 500, then the probable Eddy current304 is greatly reduced because the extent of the electromagnetic field(not shown) is related to amount of the Eddy current 304 that is inducedto the conductive coating 300. In this example, the area 500 may beconstructed to provide maximum impedance to the induced Eddy current304.

With continuing reference to FIG. 5A, the area 500 may include a portionof the conductive coating 300. In certain designs, the slots 308 maycover not only the conductive coating 300 but may also extend orpenetrate the full metal chassis 204 for portable device 102. In animplementation, no grounding point 502 is placed or inserted in the area500. In this implementation, a high coupling (e.g., coupling coefficientof 0.0846) may result.

With continuing reference to FIGS. 5B to 5D, one or more groundingpoints 502 are inserted or placed to connect the area 500 to the rest ofthe conductive coating 300. For example, FIG. 5B may include a groundingpoint 502-2 to provide ESD protection to the coil antenna 200. In thisexample, the grounding point 502-2 may be located in a middle of atleast one side of the area 500. In an implementation, the area 500 maydefine a rectangular shape to adopt rectangular configuration of thecoil antenna 200. In this implementation, the middle of the at least oneside of the area 500 may include any of four sides that define aperimeter (i.e., outer portion) of the area 500. For example, in FIG.5C, the grounding points 500-2 and 500-4 may be located at the middle ofopposite sides of the rectangular area 500. The grounding points 500-2and 500-4 may connect the area 500—where the slots 308 areconstructed—to the rest of the conductive area 300. To this end, a lowercoupling coefficient may be produced as a result.

In another example such as, in FIG. 5D, grounding points 502-6 and 502-8may be added to the grounding points 500-2 and 500-4. In this example,the grounding points 502-2, 502-4, 502-6 and 502-8 are located at themiddle of the four perimeter sides of the rectangular area 500. Thepresence of four grounding points 502 may decrease the couplingcoefficient (e.g., coupling coefficient of 0.0731) for the coil antenna200. In other words, the configuration illustrated in FIGS. 5B to 5D mayallow integration of the coil antenna 200 to the portable device 102without introduction of any other materials, such as a ferrite (notshown) that may be inserted between the coil antenna 200 and metalliccomponents (not shown). Furthermore, the configuration illustrated inFIGS. 5B to 5D may allow ESD protection to pass ESD regulatoryrequirements.

FIGS. 6A and 6B illustrate example slot 308 configurations in theconductive coating 300 in order to provide high impedance to the Eddycurrent 304. With continuing reference to FIG. 6a , the slot 308 may beconfigured in such a way that the direction of each slot 308 in the area500 is approximately perpendicular to assumed direction of the Eddycurrent 304. For example, when the Eddy current 304 starts at point 600,flows through a straight path and then bends in direction up to point602, the slot 308 may be constructed to adopt and follow the straightpath and curvature direction of the Eddy current 304 from the point 600to the point 602. In this example, some of the slots 308 may beconstructed to include right angles 604 to provide the perpendicularconfiguration of the slots 308 with regard to the assumed direction ofthe Eddy current 304.

With continuing reference to FIG. 6B, the slots 308 with right angles604 as discussed in FIG. 6A, are replaced by straight slots 308. Forexample, the slots 308 may be configured to be perpendicular to theassumed direction of the Eddy current 304 without bending the slots 308with right angles 604. Instead, the direction of the slots 308 may beadjusted to maintain perpendicular configuration with regard to curvingdirection of the Eddy current 304. In an implementation, the slots 308may include segments or slices—of conductive coating 300—that are cutout to form the high impedance area 500.

FIG. 7 shows an example process chart 700 illustrating an example methodfor integrating a NFC antenna at a full metallic chassis portable deviceto facilitate near field communications. The order in which the methodis described is not intended to be construed as a limitation, and anynumber of the described method blocks can be combined in any order toimplement the method, or alternate method. Additionally, individualblocks may be deleted from the method without departing from the spiritand scope of the subject matter described herein. Furthermore, themethod may be implemented in any suitable hardware, software, firmware,or a combination thereof, without departing from the scope of theinvention.

At block 702, constructing one or more slots in a chassis is performed.In an implementation, the one or more slots (e.g., slots 308-2, 308-4,etc.) may be constructed in a conductive coating (e.g., conductivecoating 300) of a plastic chassis (e.g., chassis 204) in a portabledevice (e.g., portable device 102). In another implementation, the oneor more slots 308 may be constructed in the conductive coating 300 andextend up to full metal chassis 204 in case of Ultrabooks design. Inother words, the one or more slots 308 protrude to surface of the fullmetal chassis 204.

At block 704, directing the one or more slots to be perpendicular withregard to direction of Eddy current is performed. In an implementation,an assumed direction of the Eddy current (e.g., Eddy current 304) mayinclude an opposite direction to the direction of injected current in acoil antenna (e.g., coil antenna 200). For example, if the direction ofthe injected current in the coil antenna 200 is clockwise, then thedirection of the Eddy current 304 is counter-clockwise.

At block 706, grounding at least one side of an area covered by the oneor more slots is performed. In an implementation, the coil antenna 200may include a continuous loop of coil to form a rectangular ring shapedcoil antenna 200. The rectangular ring shaped coil antenna 200 mayradiate electromagnetic fields sufficient to induce an Eddy current(e.g., Eddy current 304) within the area (e.g., area 500) covered by theone or more slots 308. In an implementation, at least one side of thearea 500 may be grounded to provide ESD protection to the coil antenna200.

At block 708, radiating the electromagnetic field by the coil antenna isperformed. In an implementation, the coil antenna 200 may be embeddeddirectly underneath the conductive coating 300. The conductive coating300 may be integrated to the chassis 204 of the portable device 102. Inan implementation, the coil antenna 200 may radiate the electromagneticfield during NFC related operations.

At block 710, inducing the Eddy current is performed. In animplementation, the radiated electromagnetic field may induce the Eddycurrent 304 to the conductive coating 300.

At block 712, providing high impedance to the induced Eddy current isperformed. In an implementation, the one or more slots 308 may providehigh impedance to the Eddy current 304. The high impedance may begenerated by the perpendicular configuration of the one or more slots308 to the assumed direction of the Eddy current 304.

Realizations in accordance with the present invention have beendescribed in the context of particular embodiments. These embodimentsare meant to be illustrative and not limiting. Many variations,modifications, additions, and improvements are possible. Accordingly,plural instances may be provided for components described herein as asingle instance. Boundaries between various components, operations anddata stores are somewhat arbitrary, and particular operations areillustrated in the context of specific illustrative configurations.Other allocations of functionality are envisioned and may fall withinthe scope of claims that follow. Finally, structures and functionalitypresented as discrete components in the various configurations may beimplemented as a combined structure or component. These and othervariations, modifications, additions, and improvements may fall withinthe scope of the invention as defined in the claims that follow.

The following examples pertain to further embodiments. A portable devicecomprising: one or more processors; a memory configured to theprocessors; a near field communications (NFC) antenna configured to theprocessors wherein the NFC antenna is integrated underneath a metalchassis of the portable device, the metal chassis is constructed toinclude one or more slots that are perpendicular to Eddy current inducedby the NFC antenna.

In an implementation, wherein the metal chassis includes an embedded orattached conductive coating, the conductive coating is located betweenthe metal chassis and the NFC antenna.

In an implementation, wherein the one or more slots are constructed toinclude elongated slices that extend from the conductive coating andpenetrate the metal chassis.

In an implementation, wherein the one or more slots define an area inthe conductive coating, the area includes one or more grounding pointsto provide electrostatic discharge (ESD) protection.

In an implementation, wherein a grounding point for an area defined bythe one or more slots is located at a middle of a perimeter side of thearea.

In an implementation, wherein the one or more slots define an area inthe conductive coating, the area covers approximate extent ofelectromagnetic fields that induce the Eddy current to the conductivecoating.

In an implementation, wherein the one or more slots define an area inthe conductive coating, the area includes a coil antenna configuration.

In an implementation, wherein the one or more slots transform theconductive coating to be a transparent conductive coating for the NFCantenna to increase NFC field strength.

In an implementation, wherein the Eddy current induced in the conductivecoating includes an opposite direction to a current injected in the NFCantenna.

In an implementation, wherein the Eddy current induced in the conductivecoating includes a curvature direction and the one or more slots areconfigured to follow the curvature direction of the Eddy current inmaintaining the perpendicular configuration.

In an implementation, wherein the coil antenna is made out of a printedcircuit board (PCB), a flexible printed circuit (FPC), a metal wire,created through a laser direct structuring (LDS) process, or directlyembedded to the metal chassis and underneath the conductive coating.

In an implementation, a near field communications (NFC) antennacomprising: a continuous loop of coil antenna that is integratedunderneath a chassis of a portable device, the chassis is constructed toinclude one or more slots to provide high impedance to a current thatflows in perpendicular direction to the one or more slots; and an NFCmodule to tune the coil antenna.

In an implementation, wherein the chassis is a metal chassis thatincludes an embedded or attached conductive coating, the conductivecoating is located between the metal chassis and the coil antenna.

In an implementation, wherein the one or more slots are constructed toinclude segments that extend from the conductive coating to the metalchassis.

In an implementation, wherein the current that flows in perpendiculardirection to the one or more slots includes an induced Eddy current inthe conductive coating.

In an implementation, wherein the one or more slots define an area inthe conductive coating, the area includes one or more grounding pointsto provide electrostatic discharge (ESD) protection.

In an implementation, wherein a grounding point for an area defined bythe one or more slots is located at a middle of a perimeter side of thearea.

In an implementation, wherein the one or more slots define an area inthe conductive coating, the area covers approximate extent ofelectromagnetic fields that induces the current that is perpendicular indirection to the one or more slots.

In an implementation, wherein the one or more slots defines an area inthe conductive coating, the area includes a configuration to adopt coilantenna configuration.

In an implementation, wherein the one or more slots transform theconductive coating to be a transparent conductive coating for the coilantenna to perform NFC related functions.

In an implementation, wherein the current includes a curvature directionand the one or more slots are configured to follow the curvaturedirection of the current to maintain perpendicular configuration.

In an implementation, wherein the coil antenna is made out of a printedcircuit board (PCB), a flexible printed circuit (FPC), a metal wire,created through a laser direct structuring (LDS) process, or directlyembedded to the chassis and underneath the conductive coating.

In an implementation, a method of integrating a near fieldcommunications (NFC) antenna to a metallic chassis portable devicecomprising: providing one or more slots in the metallic chassis, the oneor more slots are constructed to extend from the metallic chassis to aconductive coating underneath the metallic chassis; grounding at leastone side of an area in the conductive coating that is defined by the oneor more slots; inducing a current to the area defined by the one or moreslots; providing high impedance to the induced current by configuringthe one or more slots to be perpendicular in direction to the inducedcurrent.

In an implementation, wherein the induced current is an Eddy currentthat flows in opposite direction to an injected current injected in theNFC antenna.

In an implementation, wherein the providing the one or more slotsincludes construction of segments within the area in the conductivecoating and extends to the metallic chassis.

In an implementation, wherein the grounding includes connecting the areato the conductive coating to maintain electrostatic discharge (ESD)protection.

In an implementation, wherein the grounding at least one side includes agrounding point that is located at a middle of a perimeter side of thearea.

In an implementation, wherein the area in the conductive coatingincludes a configuration that adopts configuration or shape of the NFCantenna.

In an implementation, wherein the Eddy current includes a curvaturedirection and the one or more slots are configured to follow thecurvature direction of the Eddy current to maintain perpendicularconfiguration.

In an implementation, further comprising radiating electromagneticfields by the NFC antenna to create the Eddy current.

What is claimed is:
 1. A device comprising: a metallic housingsubstantially enclosing an interior volume of the device, the interiorvolume including: a processor; a near field communications (NFC) module;and an NFC antenna that includes a coil antenna mounted along a planarsurface of the metallic housing, wherein the metallic housing includes aslot formed on the planar surface, wherein at least a substantial partof the slot is perpendicular to a current direction of current through asegment of the coil antenna.
 2. The device of claim 1 further comprisinga display mounted to the metallic housing.
 3. The device of claim 1wherein the slot intersects the segment of the coil antenna if viewedalong an axis perpendicular to the planar surface.
 4. The device ofclaim 1 wherein the slot is aligned along a first direction, themetallic housing further comprising: a second slot aligned along asecond direction parallel to the first direction and perpendicular tothe current direction of the current through the segment of the coilantenna.
 5. The device of claim 1 wherein the slot is part of a firstplurality of slots aligned along a first direction and perpendicular tothe current direction through the segment of coil antenna; and a secondplurality of slots aligned along a second direction and perpendicular tothe current direction of the current through the segment of the coilantenna.
 6. The device of claim 1, wherein the NFC antenna comprises acoil antenna having a first side, a second side, a third side, and afourth side and wherein the slot is aligned with the first side of thecoil antenna; further comprising: a second slot aligned perpendicular toa current direction of current through a current direction of a segmentof the second side of the coil antenna; a third slot alignedperpendicular to a current direction of current through a currentdirection of the segment of the second side of the coil antenna; and afourth slot aligned perpendicular to a current direction of currentthrough a current direction of the segment of the second side of thecoil antenna
 7. The device of claim 1 wherein the slot is part of aplurality of slots arranged in a pattern that radiates out from asubstantially rectangular region.
 8. The device of claim 1 wherein theNFC antenna has four sides and is substantially rectangular and whereinthe slot is part of a plurality of slots that include slots positionedover and perpendicular to each of the four sides of the NFC antenna. 9.The device of claim 1 wherein the device comprises a handheldcommunications device, a mobile phone, a smartphone, a tablet, or alaptop
 10. A device comprising: a metal chassis that forms at least amajority of the exterior surface of the device and that providessubstantial structural integrity to the device; a processor mountedwithin the metal chassis; a near field communications (NFC) modulemounted within the metal chassis; and an NFC antenna that includes acoil antenna mounted along a planar surface of the metal chassis,wherein the metal chassis includes a slot formed on the planar surface,wherein at least a substantial portion of the slot is perpendicular to acurrent direction of current through a segment of the coil antenna. 11.The device of claim 10 further comprising a display mounted in the metalchassis.
 12. The device of claim 10 wherein the slot intersects aplurality of segments of the coil antenna.
 13. The device of claim 10wherein the slot is along a first direction, further comprising a secondslot aligned along a second direction parallel to the first directionand perpendicular to the current direction of current through thesegment of the coil antenna.
 14. The device of claim 10, wherein the NFCantenna comprises a coil antenna having a first side, a second side, athird side, and a fourth side and wherein the slot is aligned with thefirst side of the coil antenna; further comprising: a second slotaligned perpendicular to a current direction of current through acurrent direction of a segment of the second side of the coil antenna; athird slot aligned perpendicular to a current direction of currentthrough a current direction of the segment of the second side of thecoil antenna; and a fourth slot aligned perpendicular to a currentdirection of current through a current direction of the segment of thesecond side of the coil antenna.
 15. The handheld communications devicedefined in claim 9 wherein the plurality of slots is arranged in apattern that radiates out from a substantially rectangular region. 16.The device claim 10, wherein the device comprises a handheldcommunications device, mobile phone, a smartphone, a tablet, or alaptop.
 17. A device comprising: a metallic housing; a processor mountedin the metallic housing; a near field communications (NFC) modulemounted in the metallic housing; and an NFC antenna that furtherincludes a coil antenna mounted along a planar surface of the metallichousing, wherein the metallic housing includes a slot formed on theplanar surface, wherein at least a substantial portion of the slot isperpendicular to a current direction of current through a segment of thecoil antenna.
 18. The device of claim 17 wherein the slot intersects aplurality of segments of the coil antenna.
 19. The device of claim 17wherein the NFC antenna coil has four sides and is substantiallyrectangular and wherein the slot is part of a plurality of slotspositioned over and perpendicular to the current direction of currentthrough the segment of the coil antenna.
 20. The tablet of claim 17wherein the slot is part of a plurality of slots and each slot issubstantially perpendicular to an associated adjacent portion of the NFCantenna coil.
 21. The device of claim 17 wherein the device comprises ahandheld communications device, a mobile phone, a smartphone, a tablet,or a laptop.